Field of the Invention
The present disclosure relates to a graphene-based touch sensor using triboelectric effect. The present disclosure also relates to a method for manufacturing a graphene-based touch sensor using triboelectric effect.
Discussion of Related Art
With the advance of digital technology in recent years, the electronic equipment used in everyday life has become thinner, lighter and smaller enough to carry with one hand. Therefore, the size and weight of an input device such as a keypad, keyboard, and a mouse, etc. is getting smaller and smaller to make the input device thinner and lighter. In order to maximize the visual effect and reduce the space constraint, a touch screen or touch panel is integrated with a display as an output device. Such a touch screen may be classified into a resistive type, a capacitive type, an electro-magnetic type, a SAW (surface acoustic wave t) type, an infrared type, and an ultrasonic type, etc.
Recent studies focusing on graphene used in such a touch screen or touch sensing unit have been actively conducted. Graphene is composed of a carbon mono-atomic layer having a hexagonal structure in a two-dimensional plane. It has a carrier mobility of about 200,000 cm2/Vs, a high thermal conductivity of about 5000 W/mK, and a Young's modulus of about 1 TPa. Graphene is very transparent with very good visible light transmittance. However, a graphene-based touch sensing device that has been studied so far uses a principle that resistance and conductivity changes due to graphene deformation are detected when a vertical force or tensile/compressive strain is applied thereto. The conventional graphene-based touch sensor device is a capacitive type as employed in a general touch screen. Thus, the conventional graphene-based touch sensor device has a disadvantage in that it reacts only when an electrically conductive object touches the sensor, and, further, the reactivity thereof is lowered in a high humidity environment.